As the opioid epidemic and alcohol use disorder continue to affect millions of lives worldwide, effective treatment options have become more important than ever. One medication that has proven to be highly effective in treating both opioid use disorder (OUD) and alcohol use disorder (AUD) is naltrexone. Naltrexone helps individuals manage their cravings and reduces the likelihood of relapse, supporting long-term recovery.
One of the most common questions people have about naltrexone is how long it stays in the system. Understanding how long naltrexone remains in your body can help you understand its effectiveness, dosing schedule, and potential side effects. In this comprehensive guide, we’ll explore the various aspects of naltrexone, how it works, and how long it stays in your system, as well as how different factors can influence its duration.
What is Naltrexone?
Naltrexone is a prescription medication that is used to treat both opioid dependence and alcohol dependence. It is classified as an opioid antagonist, which means it works by blocking the effects of opioids in the brain. By binding to the opioid receptors in the brain, naltrexone prevents opioids like heroin, morphine, and oxycodone from exerting their effects, including euphoria and pain relief. This makes it an effective tool in helping individuals overcome opioid addiction by reducing the desire to use opioids.
In addition to its use in treating opioid use disorder, naltrexone is also used to treat alcohol use disorder. While the exact mechanism for its effectiveness in alcohol dependence is not fully understood, naltrexone is thought to reduce cravings for alcohol and diminish the pleasurable effects of drinking, which can help people maintain sobriety.
Naltrexone is available in two forms:
- Oral tablet: This form of naltrexone is taken once a day by mouth and is commonly used for both opioid and alcohol dependence.
- Extended-release injection (Vivitrol): The injectable form of naltrexone, known as Vivitrol, is administered once a month by a healthcare provider. It provides long-lasting effects, making it a convenient option for individuals who may have difficulty adhering to a daily medication schedule.
Both forms of naltrexone are effective in supporting recovery from opioid and alcohol addiction, but how long the medication stays in the body depends on several factors, including the form of naltrexone being used, dosage, and individual differences in metabolism.
How Does Naltrexone Work?
Naltrexone works by blocking the opioid receptors in the brain, preventing the effects of opioids. Unlike opioid agonists such as methadone or buprenorphine, which partially or fully activate opioid receptors, naltrexone does not activate these receptors. Instead, it prevents opioids from binding to the receptors, thereby blocking the euphoric and sedative effects of opioid drugs.
In the case of alcohol dependence, naltrexone is believed to interfere with the brain’s reward system by blocking the endorphins released when alcohol is consumed. This reduces the pleasurable effects of drinking, making it easier for individuals to cut back on or stop their alcohol use. By minimizing cravings and reducing the risk of relapse, naltrexone plays a crucial role in helping individuals maintain long-term sobriety.
How Long Does Naltrexone Stay in Your System?
The length of time that naltrexone stays in your system depends on several factors, including whether you are using the oral or injectable form of the medication. Below, we’ll explore how long each form of naltrexone remains in the body, as well as how the medication is metabolized and excreted.
Oral Naltrexone
When taken in its oral form, naltrexone has a relatively short half-life compared to the extended-release injectable version. The half-life of a drug is the amount of time it takes for half of the drug to be eliminated from the body. For oral naltrexone, the half-life is approximately 4 to 13 hours, depending on the individual. This means that after about 4 to 13 hours, half of the naltrexone dose has been metabolized and eliminated.
Given this half-life, oral naltrexone is typically cleared from the body within 24 to 48 hours after the last dose. However, traces of the medication may still be detectable in certain biological samples for a longer period, depending on factors such as the individual’s metabolism, liver function, and the sensitivity of the testing methods used.
Extended-Release Injectable Naltrexone (Vivitrol)
The extended-release form of naltrexone, marketed under the brand name Vivitrol, is designed to provide sustained effects over an extended period. Vivitrol is administered as an intramuscular injection once a month, and its effects last for approximately 28 to 30 days. Because Vivitrol releases naltrexone slowly into the bloodstream over time, it has a much longer duration of action than oral naltrexone.
The half-life of extended-release injectable naltrexone is about 5 to 10 days. This means that it takes 5 to 10 days for half of the drug to be eliminated from the body. Even though the medication remains active for approximately a month, it can take up to two months for the drug to be fully cleared from the system after the last injection.
Metabolism and Elimination
Naltrexone is primarily metabolized in the liver. The drug is converted into an active metabolite called 6-beta-naltrexol, which also plays a role in blocking opioid receptors and reducing cravings. Both naltrexone and its active metabolite are eventually excreted from the body through the urine.
For individuals with normal liver and kidney function, naltrexone is metabolized and excreted relatively quickly. However, for individuals with impaired liver or kidney function, the metabolism of naltrexone may be slower, resulting in the medication staying in the system for a longer period of time.
Factors That Affect How Long Naltrexone Stays in Your System
Several factors can influence how long naltrexone remains in your system. These include:
- Dosage and Frequency of Use
- The higher the dose of naltrexone, the longer it will take for the body to metabolize and eliminate the drug. Additionally, the more frequently naltrexone is used, the more likely it is to accumulate in the body, which can prolong the time it takes to be fully cleared from the system.
- Form of Naltrexone (Oral vs. Injectable)
- As mentioned earlier, the form of naltrexone used plays a significant role in how long the medication stays in the body. Oral naltrexone is cleared relatively quickly, usually within 24 to 48 hours, while the extended-release injectable form can stay in the system for up to two months.
- Liver Function
- Since naltrexone is metabolized in the liver, individuals with impaired liver function may process the drug more slowly. This can result in naltrexone staying in the body for a longer period of time. Individuals with liver disease or other liver conditions should inform their healthcare provider, as they may require adjusted dosing or additional monitoring.
- Kidney Function
- Naltrexone and its metabolites are excreted through the kidneys. If an individual has impaired kidney function, the excretion process may be slower, which can cause the drug to remain in the system for a longer duration.
- Age
- Older adults may metabolize and eliminate medications more slowly than younger individuals, resulting in naltrexone staying in the system for a longer time. This is due to the natural decline in liver and kidney function that often occurs with age.
- Body Weight and Metabolism
- Individuals with higher body weight or slower metabolism may find that naltrexone takes longer to be metabolized and eliminated. Conversely, those with faster metabolisms may clear the drug more quickly.
- Other Medications
- Certain medications can interact with naltrexone, affecting how quickly it is metabolized and excreted. For example, medications that affect liver enzymes may alter the metabolism of naltrexone, either speeding up or slowing down its elimination from the body.
How Long Does Naltrexone Block Opioids?
One of the key benefits of naltrexone in treating opioid use disorder is its ability to block the effects of opioids. The length of time that naltrexone blocks opioids depends on the form of the medication:
- Oral naltrexone: When taken as a tablet, naltrexone blocks the effects of opioids for 24 to 36 hours after each dose. This means that individuals who attempt to use opioids while taking oral naltrexone will not experience the typical euphoric effects of the drugs, which can help prevent relapse.
- Extended-release injectable naltrexone (Vivitrol): The injectable form of naltrexone provides sustained opioid blockade for approximately 28 to 30 days. This makes Vivitrol a convenient option for individuals who may have difficulty adhering to a daily medication schedule.
It’s important to note that while naltrexone blocks the effects of opioids, it does not prevent the physical dangers associated with opioid use. For example, individuals who attempt to overcome the opioid-blocking effects of naltrexone by taking large amounts of opioids can still experience life-threatening respiratory depression or overdose.
Can Naltrexone Be Detected in Drug Tests?
Standard drug tests, such as those used in employment screenings or legal settings, do not typically detect naltrexone. This is because naltrexone is not an opioid, and it does not produce the same effects as opioids or other drugs of abuse. However, specialized drug tests can be used to detect the presence of naltrexone in the system if necessary.
In most cases, there is no reason for naltrexone to be included in routine drug testing, as it is a legitimate medication prescribed for the treatment of opioid and alcohol dependence. If you are undergoing drug testing and are concerned about naltrexone being detected, it is important to disclose your prescription to the testing agency or employer.
Side Effects of Naltrexone
While naltrexone is generally well-tolerated, it can cause side effects in some individuals. The likelihood of experiencing side effects may vary depending on the form of naltrexone being used (oral or injectable) and individual differences in how the body processes the medication. Common side effects of naltrexone include:
- Nausea or vomiting
- Headache
- Dizziness or lightheadedness
- Fatigue or tiredness
- Muscle or joint pain
- Irritability or mood changes
For individuals receiving the injectable form of naltrexone (Vivitrol), injection site reactions such as pain, swelling, or redness may occur. Serious side effects are rare but can include liver damage, allergic reactions, or severe injection site reactions. If you experience any concerning side effects, it’s important to contact your healthcare provider.
Conclusion
Naltrexone is a powerful medication that plays a crucial role in the treatment of opioid use disorder and alcohol use disorder. Understanding how long naltrexone stays in your system can help you manage your treatment effectively, adhere to your dosing schedule, and minimize the risk of side effects.
The length of time naltrexone remains in your body depends on several factors, including whether you are using the oral or injectable form, your liver and kidney function, and individual differences in metabolism. For most individuals, oral naltrexone is cleared from the system within 24 to 48 hours, while the extended-release injectable form can take up to two months to be fully eliminated.
If you have questions about how long naltrexone stays in your system or how the medication works, it’s important to consult with your healthcare provider. At Renew Health, we are dedicated to providing compassionate, evidence-based care for individuals recovering from opioid and alcohol addiction. Contact us today to learn more about our services and how we can support your recovery journey.
